Abstract: "pi0 measurement with the ALICE photon spectrometer in first proton proton collisions at LHC"
In ultra-relativistic heavy-ion collisions (HIC) the properties of the quark gluon plasma (QGP) can be explored,
in particular, via photon detection. Photon measurement in ALICE experiment will be performed with the high
resolution photon spectrometer PHOS. Through the measurement of photons from decay channels $pi0$ $rightarrow$ $gamma$ $gamma$,
PHOS will allow us to measure $pi0$'s over a wide transverse momentum range. $pi0$'s are an
important probe in both proton and heavy ion physics. $pi0$ production in proton proton collisions provides
an important testing for QCD and helps to constrain theoritical models. It is also considered as
a baseline for exploring the modification of hard scattering processes in heavy ion measurements. An estimation
of $pi0$ differential cross-section production in proton-proton collision is calculated in a next-to-leading order (NLO) approach.
The $pi0$ identification efficiency with the invariant mass analysis, a $pi0$ descrimina!
tion with shower shape, and a realistic $pi0$ spectrum will be presented.